Electrical measuring instrument.



T. W. VARLEY. ELECTRICAL MEASURING INSTRUMENT.

APPLICATION man JUNE 5. 1916.

I Patnted Aug. 6, 1918.

FiqS

INVENTOR Thomgs W Varlgy 7 AT'TORNEY UNI? TED WW C THOMAS w. V ELEY, on NEW YORK, N. Y., AssIG OE TO WESTINGHOUSE ELECTRIC AND MANUFACTURING oo rANY, A cOnPonATIoN OF PENNSYL ANI LECTRICAL MEASURING INs'rE MEN'r.

7 Specification of Letters Patent.

Patented'Au gf. 6, 1918.

Original application filed October 3, 1913,Seria1 1V0. 793,123. Patent No. 1,234,976, dated July 31, 1917. Divided and this application filed June 5, 1916. Serial N0. 101,716.

To all whom it may concern:

Be it known that I, THOMAS W. VARLEY, a citizen of the United States, and a resident of New York, in the county of New York and State of New York,'have invented a new and useful Improvement in Electrical Measuring Instruments, of which the following is a specification this application being a division ofapplication, Serial No. 793,123, filed October 3, 1913, now Patent No. 1,234,976, July 31, 1917..

My invention relates to electrical measuring instruments and particularly to commutating devices for such instruments.

One object of my invention is to provide a commutator cylinder for a four-pole measuring-instrument that shall be so constructed that it may be engaged by brushes disposed substantially 180 apart, to thus preclude any uneven wearing of its bearing parts. A

Another object of my invention is to provide acurrent-collecting device or brush that shall have a visible means for indicating the relative pressure of itsbrushes on the commutator cylinder.

My copending application Serial NO. 793,123, filed October 3, 1913, of which this application is a division, discloses a fourpole motormeter. It is advantageous from the stand-point of torque to utilize a fourpole meter, but the usual four-pole meter necessitates that its brushes be displaced 90. This would tend to cause the hearings to wear unevenly and, in time, to impair the operation of the meter. Of course, four brushes may be used to overcome these undesirable features, but, to do so would unnecessarily increase the friction of the instrument. In view of the above noted conditions, I provide a commutator cylinder that is divided into two parts, the respective bars of which are disposed in tandem relation and displaced 90. Thus, two brushes, that are displaced substantially 180, may be used. Since it is desirable to decrease the friction of the moving parts of motor-meters, it is desirable to observe the relative pressure of the brushes on the commutator cylinder. In order to so observe this, I provide a relatively short stifl member that is adapted to be normally in alinement with the brushes. Thus, when the brush is pressed against the commutator cylinder, the angle between the brush and the relatively stiff member will serve to indicate its relative pressure on the commutator cylinder.

Figure 1 of the accompanying drawing is a view, partially in elevation and partially in section, of an assembled armature and commutator embodying my invention; Fig.-

tion in order to constitute a double four-' pole winding. The'armature' conductorsare connected to the bars 4: of a commutator cylinder 5 comprising two parts 6 and 7 that are disposed in tandem relation. The

opposite ends of the commutator cylinder have a relative angular displacementof 90 in order that brushes 8 and 9 may be disposed 180 apart. The brushes 8 and 9 are attached to pivotally mounted blocks 10 and 11 that may be adjusted by means of thumb nuts 12 and 13 and screws 14 and 15 against the force of springs 16 and 17. Guide members 18 and 19 consisting of relatively short metal strips that are bent, at their ends, and are attached to the pivotally mounted blocks 10 and 11 in normally direct alinement with the brushes 8 and 9, respectively.

The commutator cylinder 5 may be constructed by placing an insulating cylinder 20 around the shaft 21 of the instrument and disposing the commutator bars 4 therearound and securing them to the cylinder 20 by banding means 22. Of course, it is understood that the bars 4 are so bent, at their central portions, that the respective ends are displaced 90 apart with respect to each other in order to permit two brushes to be used that are so disposed as to eliminate side thrusts on the shaft 21.

In order to determine the relative pressure of the brushes 8 and 9 on the commutator cylinder 5, it is only necessary to observe the angular relation between the guide members 18 and l9 and the brushes 8 and 9 respectively. That is, if thebrushes are not pressed against the commutator cylinder 5,

the brushes will remain in. yglirect a tlinement.

with their respective guide members.

WhileI have shown my invention in its preferred form, it will, of course, be understood that changes in thesize,. theshape and the construction may be nadewithout: de-.

parting from the spirit and scope of the invention as seti'orth in t e appended claims.

I claim, as, my invention 1., In a wattmeter, the combination with an armature, of a twopart commutator cylinder having its bars d 1splaced .90"-, and a brush for each part ofthe commutator cyl inder, v said brushes being diametrically: disposedwith respect toeach other r 2. In ;adynamogelectric machine, thecom bin'atiorr ,with a four-pole armature, of I a commutator cylinder having two parts angu-- f larly;displa ced 90;", and a brushfor each part, said brushes being displaced2 180?; with respect. to each other.

8. In .a motor, the combination with a four-pole armature, of a commutator cylinder having two parts angularly displaced 90-2, anda brushforeach part said brushes beingdisposed diametrically with respect to each other,

at. A commutator cylinder having two partsangularly disposed 90? withirespect to each other iand a brush for eachpart Lt-her,e-,

inder having its parts so disposed with respect to each other that the brushes maybe disposed diam et1 'ieally I with respect to. ea h 6. In a Wattmeter, the combination with a four-pole armature, and ,--tWo (collector brushes, of, a twoepart commutator cylinder having the bars of one part 1S0 displaced, with; respect to the bars of the other part {that; thegpressure of one; brush thereon {will new,

tral ize that: of the other 1 a 7. In, a wattmeter, the combination with a fourpole armature ,and; ltvvp, collector; brushes, of a commutator cylinder; having twoparts so disposed withrespect when other that the brushes niaybeplaced sub;

antieHyl Q"; apart.

8. Im a wattnieter, the combination with; a

four pole. .armature.,-. and ,;,tW v:1 collectOP brushes, of a commutater,icylinder having two parts so disposed with respect,to eachother that the brushes may be so placed-that;

the pressure of one on? the commutator, .cyl d r will ncH T fllZB ha Of the o herT In testimony whereof, I have hereunto.- subscribed my name this 29 day of May,

1916. t. THQMAS VARLE Washington, 3?). (2. 

